Enhancing feed fermentation in rice straw basal diets using leaf protein concentrate as a novel ruminant supplement derived from .

Background And Aim: Rice straw, a widely available agricultural byproduct globally, has significant potential as a basal diet for livestock. The major challenge lies in obtaining high-protein foliage that can be easily extracted using natural water rather than chemical solvents. This study aimed to assess the ability of distilled water to extract protein concentrate from leaves ( Miq.) and to evaluate its effectiveness in enhancing rumen feed fermentation and digestibility in low-quality rice straw basal diets.

Materials And Methods: The study was conducted in two experimental series. Experiment 1 was designed to explore the ability of distilled water to extract protein concentrate from fresh and dry leaves by comparing it with the 0.1 N NaOH standard solvent. Experiment 2 focused on the digestibility of protein concentrates extracted from fresh leaves based on optimal findings from experiment 1. Five treatments consisting of 0.5% and 1.0% protein concentrate and two extractants (distilled water and 0.1 N NaOH) were used to extract protein from leaves. These extracts were then added to rice straw-based diets. Rice straw without supplements was used as a control. The treatments were arranged using a randomized complete design with five replicates.

Results: The results of experiment 1 showed that distilled water was superior to 0.1 N NaOH for extracting protein concentrate from fresh leaves, as revealed by higher dry matter, protein yield, total amino acids (AA), and total essential AA (EAA) production. For experiment 2, supplementation with distilled water-extracted protein concentrates successfully increased rumen fermentation and digestibility in rice straw basal diets, as indicated by higher gas production, total volatile fatty acid, and microbial protein levels compared with 0.1 N NaOH.

Conclusion: Findings from this study confirm that leaf protein concentrate offers a new alternative for enhancing rumen feed fermentation and the digestibility of low-quality rice straw diets. This study implies that it is an easy, cost-effective, and environmentally friendly approach, particularly beneficial for smallholders, to extract protein concentrate from fresh leaves using distilled water and use it to enhance the quality of rice straw for ruminant feed. The limitation of this study is that the supplement was established using digestibility under controlled laboratory conditions, which does not reflect real rumen conditions. Therefore, further studies using digestibility in ruminant animals are required to confirm the ability of the protein extracted from to enhance rumen feed fermentation in low-protein basal diets.